Lyle Hoover’s twin brother and Dwayne Hoover’s stepbrother. Kyle and Lyle are the biological children of Dwayne’s adoptive parents, who hadn’t been able to conceive until after they adopted Dwayne, a “common phenomenon” it seems. As babies, Kyle and Lyle would “suck each other’s thumbs,” and they still live next door to each other in identical ranch houses. Kyle is the quiet twin, and he “hasn’t spoken a thousand words since 1954.” Together with Dwayne, Kyle and Lyle run the Sacred Miracle Cave, a local tourist attraction that is being taken over by the toxic industrial waste from Barrytron, Ltd. As the waste fills the cave and threatens to cripple their business, Lyle and Kyle respond by opening fire on it with Browning Automatic Shotguns. Of course, this only makes the problem worse, but Kyle and Lyle don’t care about the environment—they only care about the cave because it is their sole source of income. Their ridiculous solution only addresses the pollution that threatens their cave, not the source of the pollution, which reflects the efforts of those in mainstream American society who refuse to confront environmental problems directly and instead treat only the symptoms of pollution.